Relay counter



Oct. 23, 1956 F T JOHN 2,767,921

RELAY COUNTER Filed April 5, 1952 N INVENTOR. N QI FMA/K T dwf/v BY @miMJ@ M ,0,5 Mvg/mfp.;

United States Patent O RELAY COUNTER Frank T. `lohn, State College, Pa.,assignor, by mesne assignments, to Research Corporation, New York, N.Y., a corporation of New York Application April 5, 1952, Serial No.280,796

11 Claims. (Cl. 23S-92) It is among the objects of this invention toprovide a counter that will count electrically any predetermined numberof current pulses of random length occurring at random intervals in animpulse receiving circuit, that will store the count electrically andindicate the total count stored at any given moment, and that willindicate any loss of the stored count because of electrical ormechanical failure.

Still further objects of this invention are to provide a counter of thetype referred to, which requires a minimum current drain on the powersupply, which operates at a speed not limited by the circuitconfiguration but only by the characteristics of the electrical devicesemployed therein, and which is adapted to be used as a register and forinserting any predetermined figure in the counter before the start ofthe counting operation.

In accordance with this invention, the counter comprises at least oneset of relays, each set including a series of impulse relays and anequal number of holding relays both types of relays arranged to operatesuccessively in cyclic sequence. When any impulse relay is energized bya pulse of current in the impulse receiving circuit, its correspondingholding relay is also energized by a holding circuit, locking itselfinto that circuit and, at the same time, unlocking and disconnectingfrom that circuit the immediately preceding holding relay and making apotential connection between the next succeeding impulse relay and theimpulse receiving circuit, so that the latter relay will be energized bythe next pulse to be counted. In this way, successive pulses of currentin the impulse receiving circuit energize the successive impulse relaysin cyclic sequence. When more than one set of relays is used, provisionis made for generating a new current impulse at the end of each cycle ineach set and for transferring that impulse to the next set, so that thesystem can be adapted to count units, tens, hundreds, etc.

The accompanying drawing is a circuit diagram of a counter embodyingthis invention; this counter has a capacity for counting up toninety-nine in the decimal system, which is sufficient to illustrate theoperation of the device.

The circuit shows a set of units counting relays on the left and a setof tens counting relays on the right. Each set includes ten set-up orimpulse relays, designated by the letter S followed by the numbers to 9in the units counting set and by the numbers 0G to 90 in the tenscounting set. Each set of relays also includes a series of memory orholding relays, designated by the prex M followed by t'ne same number asthat used to designate the corresponding impulse relay. It will be notedthat there is one holding relay for each impulse relay in each set. Tosimplify the drawing, some of the intermediate relays in each set havebeen omitted, as indicated by the broken line circuit connections; but,since these intermediate relays are interconnected in the same manner asthe other relays shown, their omission is not material to anunderstanding of this disclosure.

In the middle of the drawing, there is shown a zero ICC reset relay Zand a carry relay C, the functions of which will be explained below.

All of the relays shown in the drawing include an energizing coil andtwo switches, each switch having an armature and a normally open orclosed Contact, the armatures of any one relay being mechanically linkedtogether in the usual manner. All of the relays shown in the drawing arerepresented in their released positions, which are assumed when nocurrent is flowing through their coils.

At the extreme left of the drawing, there is shown a source of currentin the form of a battery 11, one terminal of which is grounded and theother terminal connected through a pulsing switch 12 to a conductor 13.For the purposes of this disclosure, thesuccessive manual closings ofthe pulsing switch 12 represent the operations to be counted, but itwill be understood that this switch, or any other equivalent device forgenerating current pulses, can be made responsive to the occurrence ofany other operations that it may be desired to count. Upon each closingof the pulsing switch, a pulse of current will be delivered to theimpulse receiving circuit, which includes the conductor 13 and thevarious impulse relays in the units counting set that are successivelyconnected in that circuit as hereinafter described.

Before the system is ready to count pulses in the irnpulse receivingcircuit, it is necessary to energize momentarily the zero reset relay Zfor the purpose of clearing any count already stored in the device andfor initially energizing the zero holding relays Mtl and Milt). Abattery 14 (located at the top center of the drawing), having one of itsterminals grounded and the other connected to a manual switch 16,supplies the current for energizing the zero reset relay Z through aconductor 17 when switch 16 is closed. When relay Z is energized, itsnormally closed contacts 18 and 19 are opened. The opening of contact 19disconnects the holding relays M2 to M9, inclusive, in the unitscounting set from a holding circuit, which has a source of currentrepresented by a battery 21 (located near the zero reset relay). lf anyof those holding relays should happen to be energized, storing the countof a previous operation of the device, they are now released. Similarly,the opening of Contact 18 disconnects from the holding circuit theholding relays M10 to M in the tens counting set, and also holding relayM1 in the units counting set. However, the opening of the foregoingcontacts 18 and 19 does not affect the configuration of holding relaysM0 and M00, which, if they are not already energized, will now beenergized through the closing of normally open contacts 22 and 23,respec* tively, of relay Z. Relay M0 is so energized in the followingmanner: current ows from the battery 21 through a conductor 24, nowclosed contact 22, and a conductor 26 to the coil of impulse relay S0 inthe units counting set; the other side of that coil is connected toground through a conductor 27 and the normally closed contact 28 ofrelay S9; relay S0 is accordingly energized and the armatures of its twoswitches move down, closing their normally open contacts 29 and 31; withthe closing of contact 31, current flows from ground through a conductor32 to the coil of holding relay Mtl, which is also connected to theungrounded terminal of a battery 33.

As relay M0 is energized, the armatures of its two switches move down toclose their normally open contacts 34 and 36. With the closing ofcontact 34, the coil of relay M0 secures an additional connection toground through the normally closed contacts of the lower switches of thesucceeding holding relays M1 to M9. That additional connection locksrelay M0 in the holding circuit after relay St) is released by therelease of relay Z on the opening of switch 16. In similar fashion, theclosing of contact 23 of the zero reset relay Z will `pulse relay isreleased at the end of the pulse input.

3 energize impulse relay Set) and holding relay M in the tens countingset, and the latter relay will be locked in the holding circuit in thesame manner as relay M0.

When the system has been reset to zero, as above described, by closingand opening switch 16, it is ready to count the pulse imputs produced inthe impulse receiving circuit by successive closings of pulsing switchl2. With the irst pulse input, current ows from battery ll throughconductor i3 and the now closed contact 36 of holding relay M0 to thecoil of impulse .relay Sl, which is also connected to ground throughnormally closed contact 37 of relay S0. Relay S1 is now energized, andits normally open contacts 33 and 39 are closed. The closing of contact39 connects one side of the coil of relay Ml to ground, the other sideof that coil being connected through conductors 4l and 42 and nowV losedcontact 18 of zero reset relay Z to the ungrounded terminal of battery2l. Relay M1 is accordingly energized when relay Sl is energized.

With the energizing of relay M1, the armatures of its two switches movedown to close normally open contacts 43 and Maand to open normallyclosed contact 46. The closing or" contact 43 locks relay M1 in theholding circuit; and the closing of contact 44 connects one side of thecoil of relay S2 with the impulse receiving circuit. The other side ofthat coil, however, is not connected in that circuit, and relay S2 isnot energized, so long as relay Si remains energized and its normallyclosed Contact i7 remains open (as it does until the end of the rstpulse input). The opening of the contact 46, when relay Ml is energized,disconnects holding relay M0 from the holding circuit. As that relay isreleased, it opens contact 36, through which relay Sl initially receivedcurrent from the impulse receiving circuit. As soon as .it wasenergized, however, relay S1 connected itself in that circuit through analternate conductor path represented by its closed contact 38 and byconductors 4S and 49. This alternate connection of relay S1 to theVimpulse receiving circuit is a locking connection that keeps relay S1energized so long as a pulse of current is llowing in the impulsereceiving circuit. The purpose of this locking connection is to keepcontact 47 open for the duration of the lirst pulse input so that relayS2 cannot also be energized by that pulse.

When pulsing switch l2 is opened, the rst pulse input ends. Relay S1 isthen released, but relay Ml remains energized, because or" the holdingcircuit connection through its closed contact 43. Its normally opencontact fifi is also closed, as is contact 47 of relay S1,thereby'connecting impulse relay S2 to the impulse receiving circuit.Relay S2 will accordingly be energized when the second pulse input isgenerated by the second closing of pulsing switch 12.

From the foregoing description and from the circuit diagram, it will beclear that as each successive impulse relay Sl, S2, S3, etc. in theunits set, is energized by successive pulses in the impulse receivingcircuit, a corresponding holding relay Ml, M2, M3, etc. will also beenergized and lock itself into the holding circuit, at the Y same timedisconnecting the preceding holding-relay from the circuit and partiallyconnecting the next subsequent impulse relay in the impulse receivingcircuit, that partial connection being completed only when the precedingim- In other words, each successive pulse input in the impulse receivingcircuit operates successive impulse relays in numbered sequence in theunits set of relays, and the accumulated units count is stored in acorresponding memory or holding relay, which is locked in a separateholding circuit until the next pulse inpuet actuates the next impulserelay and the new count is stored in the next Vholding relay.

At the end of the lirst nine pulses in the impulse receiving circuit,relay M9 will alone be energized (storing the units count of nine) inthe units set of relays; and

its contacts 51 and 52 will be closed. When the tenth pulse imputoccurs, current will ilow through conductor 13, closed contact 52, andconductors 53 and 26 to energize relay Sli in the same way as it waspreviously energized by current owing in conductor 26 when the zeroreset relay Z was operated by the closing of switch 16. Holding relayMt) will then be energized and the rst cycle in the units counter willhave been completed. At the same time, the current owing in conductor 32that energizcs relay Mtl will also flow through a conductor 54 toenergize the carry relay C, opening its normally closed contact 56 andclosing its normally open contact 57. The opening of contact 56disconnects relay M9 from the holding circuit. With the closing ofContact 57, a new current pulse llows from a battery 53 through aconductor 59 and closed contact el of holding relay Mill? (which wasenergized by the zero reset relay Z at the beginning of the operationdescribed herein) to energize relay Si@ in the tens counting set ofrelays. Similarly, on each subsequent tenth pulse in the impulsereceiving circuit controlled by pulsing switch 1?., a new pulse ofcurrent will be generated by the carry relay C ,and delivered to thesecond set of relays through conductor 59, and those relays will beenergized in the same way and in the same cyclic sequence as those inthe units set.

When ninety-nine pulses have been counted` relay M9 in the unitscounting set and relay M99 in the tens counting set will both beenergized. The next pulse input produced by pulsing switch l2 willoperate the carry relay C, thereby resetting the units counting set tozero as already described. Relay C will also deliver a tenth new pulseto conductor 59 in the tens counting set. Since relay M in that set isenergized and its normally open contact 62 is now closed, this new pulsewill be routed through conductors 63 and 64 to the zero reset relay Z.The energizing of that relay will reset the relays in the tens countingset to their zero positions, as previously described. The entire systemwill accordingly be reset and made ready to count a new cycle ofoperations on each tenth pulse generated by carry relay C.

For counting to numbers higher than ninety-nine, the last describedpulse in conductor 64, which is the tenth pulse generated by the carryrelay C and occurs on every one-hundredth closing of switch l2, can berouted through a terminal 65 to a third set of hundreds counting relayssimilar to those in the second set. And it will be clear to thoseskilled in the art that still further sets of relays may be cascaded toincrease the counting capacity of the system to any desired figure.

The lower armature of each holding relay in both sets is shown in thedrawing in the normally raised position that is assumed when the coilsof the respective relays are deenergized. However, when the system is inoperation, one holding relay in each set will always be energized,except when mechanical or electrical failure, or in some cases thereceipt of an improper pulse input, may create a condition in which allof those relays are 1n their released positions. Should that conditionoccur, provision is made for warning the operator by a signallingdevice, such as an error light 7l, in a circuit that is closed only whenall of the holding relays in either set are deenergized. Such a circuitis shown in the drawing, where the light '7l is connected to a source ofcurrent in series with the lower armatures of the holding relays in eachset when those armatures are in their raised positions. It is a featureof this invention that 'this error-indicating function is carried outwithout the use of any relay armatures or contacts in addition to thoserequired to carry out the normal counting operations of the system,except contacts 35 and 75' of relays Mtl and M00, respectively.

As previously stated, the total count at any given time is stored in oneof the memory or holdingrelays in each set. To indicate that count, tenoutput terminals are provided (extending across the bottom of thedrawing) for each set of relays, numbered 0, l, 2, etc., for the unitsets and 00, 10, 20, etc., for the tens sets. Each output terminal isconnected to a conductor in the holding circuit of the correspondinglynumbered holding relay and the conductor is connected to ground whenthat relay is energized, first through the upper switch of thecorresponding impulse relay and then through the locked lower switch ofthe holding relay. It will be obvious that each output terminal can beconnected to an external circuit, including an appropriate indicatingdevice, which will indicate the stored count at any given moment in eachset of relays.

It is an advantage of this invention that the counter circuit hereindescribed is particularly suited to being used as a storage register.For this operation, the zero reset relay Z is not closed, as it isbefore the start of the normal counting operation, and all of the relaysin each set are initially in this released position. The proper count isentered in each set of relays by an input pulse rom an external circuitdelivered to one of the output terminals referred to above. For example,if it is desired to register a count of three in the counter, thatoperation may be carried out by a single input pulse from an externalground source to the terminal 3. That pulse will energize the holdingrelay M3, which will then lock itself in the holding circuit; and thecounter will then count additional pulses produced by pulsing switch 12.Of course, the same count of three could be stored in the system byoperating the zero reset relay, as previously described, and followingthat operation by three successive closings of the pulsing switch 12.

lt is a further advantage of this invention that there is a minimumamount of current drain on the power supply during the operation of thecounter. Before receiving the starting impulse from the zero reset relayZ, no current at all is required by the system, despite the fact thatthe operations to be counted, represented by successive closings of thepulsing switch 12, may be going on. Until one of the holding relays isfirst energized and locked in the holding circuit, pulsing switch 12 canbe repeatedly closed without affecting any relay in the system orcausing any current to flow in the impulse receiving circuit. During theoperation of the device, the storage of the accumulated count at anytime exacts a maximum current drain from the holding circuit equal tothe requirements of only one relay in each set of relays. Likewise, themaximum current drain on the impulse receiving circuit is limited tothat required for operating one impulse relay in the units set.

it is a still further advantage of the invention, as will be apparent tothose skilled in the art, that the speed with which the counter operatesis limited only by the type of relays used in the circuit and not by thecircuit itself. Moreover, the pulses being connected can be of randomlength separated by random intervals, because only one impulse relay onany set is energized during the continuance of any pulse input, andbecause the count at any given time is stored during the intervalbetween pulses in a holding relay that is locked in a separate holdingcircuit until the next pulse input is received.

lt will be noted that the coil of holding relay M1 is connected tobattery 21 through conductors 41, and 42 and normally closed contact 18of zero reset relay Z, while the subsequent holding relays M2 to M9 inthe units set are connected to the same source of current throughnormally closed contact 56 of carry relay C. The reason for providing adifferent connection for relay Mil is that holding relay M0 and carryrelay C remain energized, and contact 56 of the latter relay remainsopen, until relay M) is unlocked from its holding circuit by theenergizing of relay M1. Therefore, relay M1 will not operate unless itis connected to its holding circuit by a conductor path that isindependent of the configurations of relay M0 and carry relay C.

While the counter circuit herein described is adapted to count in thedecimal system, it will be understood that this invention is equallyadapted to count in any other system of numeration by using anappropriate number of impulse and holding relays in each set of relays,and by cascading the necessary number of sets.

It will be apparent to those skilled in the art that the functions ofthe carry relay C in unlocking holding relay M9 at the end of each cyclein the units counter and at the same time generating a new current pulseand transmitting it to the tens counter may be performed with equaleffectiveness by holding relay M0, because carry relay C and holdingrelay M0 are both energized and locked in the holding circuit at thesame time and are both released at the same time. Accordingly, if thetwo switches of relay C are added to those of relay M0, the opening andclosing of contacts 56 and 57, functions previously carried out by carryrelay C, will be performed at the same times and for the same purposesby relay M0.

Similarly, the functions of zero resetting relay Z in releasing holdingrelay M and in energizing impulse relay S00 on each hundredth pulseinput to the impulse receiving circuit (i. e., on each tenth pulsegenerated by the units counter set) can be equally well carried out byholding relay Milt), provided conductor 64 is connected to the coil ofimpulse relay S00 and the lower switch of relay Z is transferred toholding relay M60. Relay S90 will then be energized on the tenth pulsereceived by the tens counter set and will in turn energize relay M00;and the added switch of the latter relay will then open Contact 18, todisconnect battery 21 from the holding relay M90. However, zeroresetting relay Z would still be used, when it is desired to clear thecounter after any intermediate count had been completed, i. e., a countof less than one hundred, as for example, at the beginning of a newcounting operation.

As used in the appended claims, a cylic series of relays refers to aplurality of relays arranged to operate successively in endless orcyclic sequence, i. e., after all of the relays in the series have beenenergized successively the first relay is again energized and the cycleis repeated.

According to the provision of the patent statutes, I have explained theprinciple of my invention and have illustrated and described what I nowconsider to represent its best embodiment. However, l desire to have itunderstood that, within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically illustrated anddescribed.

I claim:

l. A counter for counting electrical impulses in an impulse receivingcircuit, comprising a cyclic series of impulse relays, a cyclic seriesof corresponding holding relays equal in number to the number of impulserelays, a holding circuit, means controlled by each impulse relay andoperable when that relay is energized for initially connecting thecorresponding holding relay in the holding circuit, means controlled byeach holding relay and operable when that relay is initially energizedfor locking that relay in the holding circuit and for unlocking anddisconnecting the next preceding holding relay from that circuit, andmeans controlled by each impulse relay and its corresponding holdingrelay and operable when the former is deenergized and the latter isenergized for connecting the next succeeding impulse relay in theimpulse receiving circuit, whereby after one of the holding relays isinitially energized successive current impulses in the impulse receivingcircuit will energize successive impulse relays in cyclic sequence andthe completed count at any time in each cycle will be indicated by theenergized state of the holding relay corresponding to the impulse relaythat was last energized.

2. A counter according to claim l that also includes means for initiallyenergizing one of the holding relays corresponding to a predeterminedcount before the counting operation is started.

3. A counter according to claim 1 that also includes a resetting meansfor unlocking and disconnecting from the holding circuit all but one ofthe holding relays and for connecting that one holding relaycorresponding to a zero count in the holding circuit, whereby the nextYsubsequent impulse relay corresponding to a unit count of one willreceive the next pulse input in the impulse receiving circuit to begin anew counting 4. A counter for counting electrical impulses in an impulsereceiving circuit, comprising a cyclic series ot' impulse relays, acyclic series of corresponding holding relays equal in number to thenumber of impulse relays, each relay having an energizing coil controllf one switch that occupies an energized when i coil is energized and areleased position when the coil is deenergized, a holding circuit, thecoil of each impulse relay being connected in the impulse receivingcircuit in series with a switch in its released position of the nextpreceding impulse relay and a switch in its energized position of theholding relay corresponding to the next preceding impulse relay, thecoil of each holding relay being initially connected in the holdingcircuit through a switch in its energized position of the correspondingimpulse relay and remaining connected therein in holding circuitrelation in series with its own switch in its energized position and aswitch in its released position of the next succeeding holding relay,whereby successive impulses in the impulse receiving circuit willenergize successive impulse relays in cyclic sequence and the completedcount in any given cycle at any time will be indicated by the energizedstate of one of the holding relays.

5. A counter according to claim 4, in which the coil of each impulserelay when connected in the inmpulse receiving circuit and initiallyenergized by a current pulse therein remains connected in that circuitand enV ergized thereby for the duration of said pulse through its ownswitch in its energized position in series with a switch in its releasedposition of the next preceding irnpulse relay. Y Y

6. A counter according to claim 4 that also includes an electricalcircuit that is closed only when the switches of all of the holdingrelays arc in their released positions and electrically operated warningmeans connected in said circuit, whereby if none of the holding relaysis energized at any time during the counting operation., resulting inthe loss of the completed count in a given cycle, the warning means willbe energized to indicate that fact.

7. A counter according to claim 4, in whichlthe coil of each holdingrelay with the exception of the first and last holding relays of theseries is additionally connected in series with switch means controlledby the last holding relay of the series and is energized by the holdingcircuit only when the last holding relay of the cries is deenergized. l

8. A counter for counting electrical impulses in animpulse receivingcircuit, :comprising a series of impulse Y' relays arranged to operatesuccessively in cyclic sequence upon the occurrence of each currentpulse in the impulse receiving circuit, a series of :correspondingholding relays equal in number to the number of impulse relays `andarranged to operate successively in cyclic sequence, a holding circuit,switch means controlled by each impulse relayV when that relay isenergized by 'a pulse of current in the impulse receiving circuit forlocking that relay in the impulse receiving circuit for the duration ofthat pulse and for initially connecting the corresponding holding relaywith the holding circuit to energize that CTI holding relay and fordisconnecting the next subsequent impulse relay from the impulsereceiving circuit for the duration of that pulse, and switch meanscontrolled by each holding relay when that relay is energized forlocking that relay in the holding circuit and for unlocking anddisconnecting the next preceding holding relay from that circuit and forconnecting the next subsequent impulse relay to relieve the nextsubsequent current pulse in the impulse receiving circuit.

Si. A counter according to claim 8, which includes a resetting relay andswitch means controlled by that relay for unlocking and disconnectingfrom the holding circuit all but one of the holding relays and forconnecting that one holding relay with the holding circuit, whereby thenext s cquent impulse relay will receive the next pulse input theimpulse receiving circuit to begin a new counting cycle.

l0. A counter for counting electrical impulses in an impulse receivingcircuit, comprising a first series of impulse relays and correspondingholding relays arranged to operate successively in'cyclic sequence, aholding circuit, switch means controlled by each impulse relay when thatrelay is energized by a pulse of current in the in*- pulse receivingcircuit for locking that relay in its energized position for theduration of that pulse and for connecting the corresponding holdingrelay with the holding circuit to energize that holding relay and fordisconnect ing the next subsequent impulse relay from the impulsereceiving circuit for the duration of that pulse, switch meanscontrolled by each holding relay when that relay is energized forlocking that relay in the holding circuit and for unlocking anddisconnecting the next preceding holding relay from that circuit and forconnecting the next subsequent impulse relay to receive the nextsubsequent current pulse in the impulse receiving circuit, cycle impulsegenerating means controlled by one of the relays of the rst series forgenerating a secondary current pulse when a cycle has been completed inthe rst series of relays, a second series of impulse and holding relayssimilar to the tir-st series, switch means controlled by each impulserelay of the second series when that relay is energized by a secondarycurrent pulse for initially connecting the corresponding holding relayof that series with the holding circuit and for disconnecting the nextsubsequent impulse relay of that series from the secondary pulsegenerating means for the duration of said secondary pulse switch meanscontrolled by each holding relay of the second `series when that relayis energized for locking that relay in the holding circuit and forunlocking and disconnecting the next preceding holding relay of thatseries from that circuit and for connecting the next subsequent impulserelay of that series to receive the next subsequent current pulse fromthe impulse generating means of the first series, whereby the number ofimpulse relays energized in the second `series will be a function of thenumber of :cycles completed in the iirst series.

11. A counter according to Aclaim l0, which includes a relay. and switchmeans controlled by that relay for unlocking and disconnecting from theholding circuit all but one of the holding relays in each series and forconnecting that one holding relay in each `series with the holdingcircuit, whereby a new counting cycle Will begin in each series.

References Cited in the le of this patent UNITED STATES PATENTS KinkheadMar. 25,

